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How to replace braking support link (bearing carrier) ball joints

5K views 11 replies 5 participants last post by  wooky_chew_bacca 
#1 · (Edited)
If you get the occasional clunk when going through a dip/gutter diagonally, it could be your brake strut ball joints.

It's a fairly easy project unless the old joints are corroded in place, like mine were.

In short, all you need to do is remove the brake support link (dogbone), replace the ball joint, and reinstall.

I learned a few tricks. The threads of the two large bolts that hold the brake support to the car can get corroded. I started long ago shooting PB Blaster in there every time I thought of it.

Be sure to measure the distance from the carrier to the control arm. I just used a tape measure along the support tube (the rod that goes forward to the lower control arm). This way you'll get the alignment back close. I would recommend having the car aligned after this project.

Remove the center link that goes across the car and attaches to each brake support. Then just unthread the ball joint threads from the support tube and remove the two bolts holding the brake support link to the body.

The manual casually mentions pushing the control arm forward to ease removal of the bearing carrier. That's an understatement. It's not easy to push forward. But it is easy to wedge an 18" breaker bar in there as shown in the pics to hold it in place. This worked perfectly. Just place it where shown and start unthreading the ball joint threads. Eventually the breaker bar will drop in place. I threaded the ball joint back in a little until the bar was firmly wedged in place and holding the lower control arm in position. Then I took out the two large bolts holding the bearing carrier to the body. After it drops down, finish unthreading the ball joint.

The manual also comically instructs to use a plastic hammer to knock out the ball joint. What a joke. I had to use a 20-ton press. And all this did was push the rubber part of the joint out. I had to bend, pry, chip and grind the metal ring away from the inside diameter of the bearing carrier. It was a pain. The years had not been kind to this part of the car.

If you don't have a press, don't worry. I discovered on the second ball joint that I could tap a screwdriver under the lip of the ball joint perimeter, bending the metal inward and away from the wall of the carrier. It wasn't too bad at all. I used a wire brush in a drill to clean up the aluminum.

I've included pics of the old joints.

Installation was a piece of cake. I applied a thin coat of Permatex 2B on the outer diameter of the new joint and the inner diameter of the support link. It was easy to tap the joint into place. Be sure to line up the split in the metal outer sleeve of the joint with the drain hole in the link.

Start threading the ball joint threads back into the support rube. As you thread, the support link moves toward the front of the car and eventually the two big bushing holes will line up with their respective holes in the body and you can insert the bolts. I torqued these down then adjusted the ball joint threads until I had the same length I measured at the beginning. Of course you have to fiddle with the length a little to get the breaker bar out.

The ball joints come with new nut clips. After tightening everything up, I shot a bunch of undercoating oil in there to hopefully slow down future corrosion.

I'm quite sure the old ball joints were original. The new ones were Meyle so I may be doing this again sooner than the 28 years I got out of the original MB parts.

Torques in NM:

Support tube clamp: 20
Bolts for center link (cross yoke): 45
Ball joint bolts: 35
Brake support to body: 80
 

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#3 ·
wish I had jammed in a support like the breaker bar when I took mine out. that puppy is HARD to move. What do you think about extending the length of travel by loosening the shock from the tower, just enough to hold the spring at minimal tension? I have the approved spring compressor but rather not get out that much pomp for this circumstance.
 
#4 ·
I doubt that will give you the movement you need. How about pulling the lower control arm forward with something? Rope, cable, block and tackle?

Or how about letting the car down and drive it backwards an inch or so with the front brakes on? It's a stretch, I know.
 
#5 · (Edited)
Another perspective from a genuine shady . . . . . tree mechanic

How I got all of that apart and pushed the lower control arm forward (and did this on two different cars) was to mark the bushing threads (big bar) with white out, count the threads later with new one on. I unthreaded the bushing almost all the way out (eye-ball using the new one) and with the rear wheels chocked I lowered the car with the pushed forward lower arm down on a block of wood to hold it. At this point I unbolted and dropped the dogbone and finished unscrewing it from the rod. Pried the old bushing out with a drewscriver working my way around. Installed the new by tapping around and around til seated with the slots up and down for drainage (I forgot about it having a drain hole :wink) Started the new into the rod a couple of good turns then bolted up the bone. I had some trouble with the new bolts and those long flat tangs with the captured nut (wouldn't screw in and a nut popped out of the tang :eek) so I used the old ones with a dab of Locktite. Raised the car off the wood block, counted the threads and ran it in to about where it needed to be til the alignment shop set it correctly. Don't forget to replace the crossbar between the bones

No fancy tools or gizmos here and a relatively easy job to do (not that I'd want to do this again any time soon)
 

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#6 ·
so a ratcheting nylon 500 lb strap to the tow hook will be what I try. It is the passenger side so spring removal is pretty easy if that doesn't work.
 
#7 ·
Strap worked, but couldn't release it by the ratchet. Razor knife released it, it was a good death.
 
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#9 ·
I've got to tackle this, what is causing the tension on the lower control arm?
 
#11 ·
I agree Mike. If you are taking out the pressure from the spring, it moves as easy.
 
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